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#Using Raspberry pi 3, kernel 4.14.76, OpenCV 4.0
import numpy as np
import cv2

image = cv2.imread("images/136_5cm.png")
output = image.copy()
gray = cv2.cvtColor(output, cv2.COLOR_BGR2GRAY)
gray = cv2.GaussianBlur(gray, (9, 9), 0)
# detect circles in the image
print('hello')
circles = cv2.HoughCircles(gray,cv2.HOUGH_GRADIENT,1.4,50, param1=80,param2=40,minRadius=10,maxRadius=30)

# ensure at least some circles were found
if circles is not None:
    # convert the (x, y) coordinates and radius of the circles to integers
    circles = np.round(circles[0, :]).astype("int")

    # loop over the (x, y) coordinates and radius of the circles
    for (x, y, r) in circles:
        r = 28
        # draw the circle in the output image, then draw a rectangle
        # corresponding to the center of the circle
        cv2.circle(output, (x, y),r , (0, 255, 0), 2)
        cv2.rectangle(output, (x -5, y - 5), (x + 5, y + 5), (0, 128, 255), -1)

    # show the output image
    cv2.imshow("output", np.hstack([image, output]))
    cv2.waitKey(0)